David Jones, the global chief executive of Havas Worldwide, has warned that advertisers who market their brands as socially responsible should fear "inherently negative" social media such as Twitter and Facebook more than getting ad campaigns banned by regulators.

Jones, who raised the issue in a discussion on consumer demand for social responsibility from brands at the Isba annual conference yesterday, said that following the downturn companies would have to work significantly harder to prove the authenticity of their brands.

"Social responsibility was one of the biggest trends before the financial and economic meltdown and it will be coming out of it," he said, speaking to MediaGuardian.co.uk after the session. "Many companies got burnt by consumers [before the downturn] because they did it tactically, greenwashing, and not as a strategic move."

Earlier this week the Advertising Standards Authority unveiled a new advertising code that included a social responsibility clause that aims to crack down on advertisers who look to "break the spirit if not the actual letter" of the rules.

Jones said that with the rise of social media, with which many companies are still grappling, brands should be more worried about consumers than trying to outmanouevre the regulator.

"Social media is inherently a more negative than a positive medium on many levels," he added. "Lots of stuff that is passed around is negative. If you are a brand or a company today you should be far less worried about broadcast regulations than digitally empowered consumers. What is an ASA sanction versus a [negative] sanction from a couple of million people if you are not authentic?"

Jones, alongside Euro RSCG chairman Kate Robertson, is about to kick off the second year of global initiative One Young World. The first, which was held in London, saw 1,000 delegates aged under 26 discuss global problems such as climate change and how the next generation will tackle them.

The initiative, dubbed a "Youth Davos" and supported by Bob Geldof and Kofi Annan, has already shown that it is a given that companies will have to be "conscious corporations" that "do good rather than just look good".

"Young digitally empowered consumers will punish those that don't [be socially responsible] and reward those that do," Jones said. "Social media has given people real power to act. Old leaders don't understand the impact of social media. It is a medium the young people of the world control."

The location of the next summit, which will be held next year, is currently the focus of a bid process between cities in the US, France, India, South Africa and Malaysia.

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